A good designer will address all relevant issues when overcoming a problem at minimum cost.

Any compromise on his ability to address the issues, overcome the problem, or create extra cost shows a compromise of his engineering ability.

The number of projects an engineer attempts bears absolutely no relation on his competence. A design engineer may take many months to design a bridge abutment, many weeks to design a crankshaft, or a few hours to design a small bracket, but none of these are necessarily done well/poorly, and none of these are indicative of his competence.